Clinical Trial Details
— Status: Recruiting
Administrative data
| NCT number |
NCT02994160 |
| Other study ID # |
STU 092014-061 |
| Secondary ID |
|
| Status |
Recruiting |
| Phase |
N/A
|
| First received |
|
| Last updated |
|
| Start date |
June 2015 |
| Est. completion date |
December 2025 |
Study information
| Verified date |
February 2024 |
| Source |
University of Texas Southwestern Medical Center |
| Contact |
Debby Noble |
| Phone |
214-648-8686 |
| Email |
debby.noble[@]utsouthwestern.edu |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Interventional
|
Clinical Trial Summary
Our goal is to temporarily implant the following groups for 540 +/- 30 days:
1. Forearm FAST electrodes
1. Five human partial hand amputees (amputated at the level of the hand) with 2 FAST
electrodes in the ulnar nerve and 2-5 FAST electrodes in the median nerve.
2. Five human hand and forearm amputees (amputated at the level of the forearm) with 2
FAST electrodes in the ulnar nerve and 2-5 FAST electrodes in the median nerve .
2. Arm FAST electrodes
1. Five human partial hand amputees (amputated at the level of the hand) with 2 FAST
electrodes in the ulnar nerve and 2-5 FAST electrodes in the median nerve.
2. Five human hand and forearm amputees (amputated at the level of the forearm) with 2
FAST electrodes in the ulnar nerve and 2-5 FAST electrodes in the median nerve.
3. Five human hand, forearm and arm amputees (amputated at the level of the arm) with
2 FAST electrodes in the ulnar nerve and 2-5 FAST electrodes in the median nerve.
Description:
Study Procedures:
Subjects will be consented during a pre-operative visit in the Plastic Surgery Clinic and
screened for participation.
Screening history and physical Potential human subjects will receive a full medical
assessment by the PI. The screening interview will focus on details of the patient's upper
extremity condition and comprehensive details of the patient's overall health status. The
screening examination will include general examination of the subject.
Pre-operative imaging and diagnostic studies MRI, x-ray, EMG/Nerve conduction studies (NCS) -
Each subject who passes the screening H&P will receive the following for their residual limb:
magnetic resonance neurogram (MRN), plain x-rays, EMG/nerve conduction studies, and
psychological assessment. Other studies will be performed in accordance with the UT
(University of Texas) Southwestern pre-operative testing protocol, and will depend on the
age/gender/medical history of the subject.
MR neurogram will provide information regarding the location and health of amputated
peripheral nerve stumps in the residual limb.
Plain x-rays will allow assessment of the bony anatomy of the amputation stump, and
suitability for nerve/muscle implants.
Electromyogram/Nerve conduction studies will include motor and sensory nerve conduction of
the median and ulnar nerves, and needle exam (voluntary activation EMG) of the residual arm,
forearm and hand muscles.
A comprehensive assessment will be completed by a licensed psychologist. This assessment is
utilized to ensure that patient is psychologically and mentally suitable to participate in
the study.
Other studies Based on UT Southwestern pre-operative testing protocol, other studies may be
required prior to surgery. CBC (complete blood count) with type and screen will be performed,
and HCG (pregnancy test) in females age 15-50. EKG will be performed in males > 40, and
females > 50. Chest x-ray will be performed in subjects with a prior history of smoking or
lung/chest injury. If surgery is scheduled for more than 90 days after this testing is
completed, another set of tests will be needed.
Patient treatment, week of surgery Subjects who have passed all screening measures and who
have completed the consent process will be seen for a routine pre-operative H&P up to 30 days
before surgery.
Prophylaxis for Methicillin-Resistant Staph Aureus (MRSA) The subject will receive mupirocin
ointment to place intranasal, to both nares, twice a day for 5 days prior to surgery.
Implantation surgery Surgery will be performed by Jonathan Cheng, MD, at Clements University
Hospital at UT Southwestern Medical Center in Dallas. Another staff hand surgeon or a hand
surgery fellow or plastic surgery resident trainee may accompany him as an assistant during
the procedure. General anesthesia will be provided by the Department of Anesthesiology at UT
Southwestern. Procedures are estimated to last 4-6 hours, and will require placement of a
standard catheter for intravenous (IV) access and a urethral (Foley) catheter for urine
output monitoring. Long-lasting neuromuscular blockade will be avoided in the anesthetic
regimen, in order to permit neuromuscular microstimulation / nerve conduction to help confirm
neural anatomy during the surgical procedure. Preoperative IV antibiotic will be administered
for infection prophylaxis. One 4-6 inch-long incision will be needed for implantation of
nerve electrodes. The implant lead wires will be tunneled under the skin for a distance, and
then placed through the skin. In the forearm-level amputees the wire exit sites may be below
or above the elbow depending on the subject's prosthesis configuration. In the arm-level
amputees the wire exit sites may be below or above the shoulder depending on the subject's
prosthesis configuration. Small counter incisions may be needed along the paths of the lead
wires to facilitate placement. The point where the lead wires exit the skin will be dressed
with a sterile/antimicrobial dressing used commonly for indwelling vascular access devices
(VAD). Following implantation, incisions will be infiltrated with bupivacaine for
postoperative analgesia and closed with sutures and skin glue. The limb will be placed in a
protective splint / immobilizer for the first 3 weeks after surgery.
Motor and somatosensory evoked potentials Nerve dissection will be performed under the
operating microscope or surgical loupes. The motor and sensory fascicular groups of the ulnar
and median nerves will be identified microsurgically as needed for the planned electrode
implantations (ulnar only, or ulnar+median) based on their predictable intraneural
topography.
Nerve electrode implantation The ulnar and median nerves will be accessed through a skin
incision (4-6 inches long). The nerves will be microdissected with 2 electrode arrays
targeted to the component fascicles of the ulnar nerve and 2-5 electrode arrays to the
component fascicles of the median nerve.
Post-operative care in the hospital Immediately following surgery, subjects will receive
routine postoperative care. Overnight hospital stay for up to 2 nights will be optional
depending on the level of pain control in the PACU following surgery. Analgesia will consist
of acetaminophen and parenteral and oral narcotics, and pregabalin or gabapentin and/or
nortriptyline as needed for neuropathic pain. The Foley catheter will be removed as soon as
possible following surgery. The IV fluids will be capped as soon as the patient demonstrates
adequate oral intake and normal fluid balance. The patient will wear sequential devices on
the legs and will walk on a scheduled basis for venous thromboembolism prophylaxis.
Prophylactic antibiotics will be administered during the hospital stay up to 24 hours after
surgery. Discharge criteria will be met when the patient demonstrates pain controlled
adequately by oral analgesics, independent ambulation, and tolerance of oral intake.
X-rays After implantation surgery, plain film x-rays will be obtained of the subject's limb
in order to establish a baseline for the position of implanted electrodes and leads.
Outpatient care The subject will be seen in clinic on a weekly basis following implantation
surgery for 3 weeks and then as needed until explantation if there is evidence of local
redness, inflammation, serous drainage or skin irritation near the incisions.
Percutaneous leads The electrode leads will be inspected at each weekly visit, and the
dressings will be changed using sterile technique based on VAD protocols. If any dressing
ever becomes wet, soiled, or leaking, the subject will be instructed to change it. After the
first 3 clinic visits wire site dressing changes will be performed by research personnel who
have been trained by the principal investigator.
Experimental data collection in implanted subjects (2 - 540 +/- 30 days)
Timing: Human physiology experiments will begin after 2 days following implantation, to allow
tissue-electrode interactions to stabilize. Subjects will have human physiology lab sessions
up to 6 times per month.
Location: Most of the human physiology experiments will take place at UT Southwestern. Some
participants may be asked to travel to the University of Minnesota Bioengineering Lab up to
10 times during the study participation period for the human physiology experiments. Subjects
also may be asked to participate in experimental sessions outside of the laboratory, in order
to measure the impact of non-laboratory environmental settings on nerve recordings and
subject perception of sensory nerve stimulation. These will take place in a controlled
environment, supervised by member(s) of the research team during experimental trials, which
may include a clinical exam room or therapy space, conference or meeting room, hotel room or
private residence. These sessions may take place one time a month, for up to 7 days at a
time.
Motor assessment: We will ask subjects to attempt to perform hand movements and positions.
The movement trials will consist of simultaneous volitional movements and positioning of both
the uninjured/sound limb and the injured/amputated "phantom" limb. We will record nerve
electrode activity during all of the movement trials.
Sensory assessment: We will also perform sensory detection and discrimination trials. Here,
the subject will be asked to report if he/she detects any sensation during microstimulation
via implanted electrodes. If they do have a sensory perception, they will be asked to
describe the quality and strength of the perception, e.g. location, touch, vibration,
temperature. Subjects may also be asked to fill out standardized sensory/pain assessments
during microstimulation and after microstimulation is turned off. Other stimulation trials
that may be done will include single or multiple electrode stimulation to see if subjects can
perceive multiple sensory percepts simultaneously.
Sensory-motor integration: After determining the subject's sensory detection and
discrimination parameters, we will ask them to perform activities using the prosthetic hand.
Microstimulation via implanted electrodes will be paired with motion or contact during task
performance in order to determine whether providing evoked sensation during prosthesis use
improves task-based performance.
Autonomic assessment: Noninvasive studies maybe performed up to 6 times to assess normal body
functions reflecting the activity of the autonomic nervous system, such as EKG
(electrocardiogram), temperature, heart rate, pulse oximetry, blood pressure, cutaneous sweat
production, and cutaneous blood flow using laser Doppler.
Explantation surgery - Will be planned for 540 +/- 30 days after implantation. If
explantation surgery is scheduled for less than 90 days from the implantation pre-operative
testing then the pre-operative testing requirement will be waived. Surgery will be performed
by the PI. General anesthesia will be provided by the Department of Anesthesiology at UT
Southwestern. Procedures are estimated to last 2-3 hours, and will require placement of a
standard catheter for IV access. Preoperative IV antibiotic will be administered for
infection prophylaxis. The previous incisions used to place nerve electrodes will be
redeveloped for access to the implanted systems. Following explantation, incisions will be
infiltrated with bupivacaine for postoperative analgesia and closed with sutures and skin
glue. Postoperative analgesia will be performed as listed above. Jonathan Cheng, MD, will see
the subject in clinic once the week following surgery and then as needed. The dressing will
be removed and replaced at the first postoperative visit. The incisions will be visually
inspected at each visit. The subject will be instructed to contact the research team by phone
on week 2 and week 3 to determine if they need to come to the clinic.
Post-participation interview - Subjects may be asked to participate in a recorded video
interview conducted by the research team to record their subjective experiences with the
study.
